A static IP address is an IP address that was manually configured for a device instead of one that was assigned by a DHCP server. It's called static because it doesn't change vs. a dynamic IP address, which does change.
Routers, phones, tablets, desktops, laptops, and any other device that can use an IP address can be configured to have a static IP address. This might be done through the device giving out IP addresses (like the router) or by manually typing the IP address into the device from the device itself.
Static IP addresses are also sometimes referred to as fixed IP addresses or dedicated IP addresses.Ach5 / Lisa Fasol
Why Would You Use a Static IP Address?
Another way to think of a static IP address is to think of something like an email address, or a physical home address. These addresses don't change—they're static—and it makes contacting or finding someone easy.
Similarly, a static IP address is useful if you host a website from home, have a file server in your network, use networked printers, forward ports to a specific device, run a print server, or use a remote access program. Because a static IP address never changes, other devices always know exactly how to contact a device that uses one.
For example, if a static IP address is set up for a computer in a home network. Once the computer has a specific address tied to it, a router can be set up to always forward certain inbound requests directly to that computer, such as FTP requests if the computer shares files over FTP.
Not using a static IP address (using a dynamic IP that does change) is a hassle if you're hosting a website, for example, because with every new IP address that the computer gets, you have to change the router settings to forward requests to that new address. Neglecting to do this would mean nobody could get to your website because the router has no idea which device in the network is the one that's serving the website.
Another example of a static IP address at work is with DNS servers. DNS servers use static IP addresses so that devices always knows how to connect to them. If they changed often, you'd have to regularly reconfigure those DNS servers on your router or computer to use the internet.
Static IP addresses are also useful for when the device's domain name is inaccessible. Computers that connect to a file server in a workplace network, for instance, could be set up to always connect to the server using the server's static IP instead of its hostname. Even if the DNS server malfunctions, the computers could still access the file server because they communicate with it through the IP address.
With remote access applications such as Windows Remote Desktop, using a static IP address means you can always access that computer with the same address. Using an IP address that changes requires you to know what it changes to so that you can use that new address for the remote connection.
Static vs. Dynamic IP Addresses
The opposite of a never-changing static IP address is an ever-changing dynamic IP address. A dynamic IP address is a regular address like a static IP is, but it's not permanently tied to a device. Instead, dynamic IP addresses are used for a specific amount of time and then returned to an address pool so that other devices can use them.When to Use a Static vs Dynamic IP Address
This is one reason that dynamic IP addresses are useful. If an ISP used static IP addresses for their customers, there'd constantly be a limited supply of addresses for new customers. Dynamic addresses provide a way for IP addresses to be reused when they're not in use elsewhere, providing internet access for more devices than would otherwise be possible.
Static IP addresses limit downtime. When dynamic addresses obtain a new IP address, any user that's connected to the existing one is removed from the connection and has to wait to find the new address. This wouldn't be a wise setup to have if the server hosts a website, a file-sharing service, or an online video game, all of which normally require constantly active connections.
In a local network, such as in a home or place of business, where you use a private IP address, most devices are probably configured for DHCP and thus use dynamic IP addresses.
The public IP address assigned to the routers of most home and business users is a dynamic IP address. Larger companies usually don't connect to the internet via dynamic IP addresses; instead, they have static IP addresses assigned to them which don't change.
Disadvantages of Using a Static IP Address
The major disadvantage that static IP addresses have over dynamic addresses is that the devices must be configured manually. The examples given above with regards to a home web server and remote access programs require you to set up the device with an IP address and properly configure the router to communicate with that specific address.
This requires more work than plugging in a router and allowing it to give out dynamic IP addresses via DHCP.
If a device is assigned an IP address of, for example, 192.168.1.110, and you go to a different network that gives out 10.X.X.X addresses, you won't be able to connect with the static IP. Instead, the device will need to be reconfigured to use DHCP (or use a static IP that works with that new network).
Security might be another downfall to using static IP addresses. An address that never changes gives hackers a prolonged time frame to find vulnerabilities in the device's network. The alternative would be using a dynamic IP address that changes and would, therefore, require the attacker to also change how they communicate with the device.
How to Get a Static IP Address
The steps for configuring a static IP address in Windows are fairly similar in Windows 10 through Windows XP. You can also set a static IP address on your phone or tablet.How to Change Your IP Address (And Why You Might Want To)
Some routers reserve an IP address for specific devices that are connected to a network. This is normally done through DHCP Reservation, and it works by associating an IP address with a MAC address so that each time that specific device requests an IP address, the router assigns it the one you chose to associate with that physical MAC address.
You can read more about using DHCP Reservation at your router manufacturer's website. Here are links to instructions on doing this on routers from popular manufacturers: D-Link, Linksys, NETGEAR, Google.
To change the network settings, learn how to log in to your router as an administrator.
Getting a static IP address for your home or business requires contacting your ISP, but it might not be an option depending on the company. Static IP address assignments for public IP addresses are normally more expensive than choosing the dynamic IP option.
Fake a Static IP With a Dynamic DNS Service
Since using a static IP address for a home network may cost more than a regular dynamic IP address, opt for both by using a dynamic DNS (DDNS) service.
Dynamic DNS services associate a changing, dynamic IP address to a hostname that doesn't change. It's like having your own static IP address but at no extra cost than what you're paying for a dynamic IP.
No-IP is one example of a free dynamic DNS service. Download their DNS update client which redirects the hostname you choose to be associated with your current IP address. This means that if you have a dynamic IP address, you can access your network using the same hostname.
A dynamic DNS service is helpful if you need to access your home network with a remote access program but don't want to pay for a static IP address. Similarly, you can host your own website from home and use dynamic DNS to ensure visitors can always access to your website.
ChangeIP.com is another free DDNS service, but there are many others.